Boiler-furnace



(No Model.) 2 Sheets-Sheet 1.

" W. I-LPEAROE.

' BOILER FURNACE.

No. 576,470. Patented Feb. 2, 1897;

Nrrnn STATES ATENT OFFICE.

IVILLIAM II. PEARCE, OF CHICAGO, ILLINOIS.

BOILER-FURNACE.

SPECIFICATION forming part of Letters Patent No. 576,470, dated February2, 1897. Application filed May 23, 1896. Serial No. 592,722- (No model.)

To all whom it 712.11, IZOILCGIIL' Be it known that I, WILLIAM II.PEARCE, a citizen of the United States, residing at Ohicago, in thecounty of Cook and State of Illinis,have invented a new and usefulBoiler- Furnace, of which the following is a specification.

Thisinvention relates to furnaces for steamboilers.

The object of the invention is to provide a furnace forsteain-boilerswhich is simple in construction and thoroughly efficientin operation.

Afurther object of the invention is to provide a furnace forsteam-boilers wherein the products of the combustion of the coal isthoronghly consumed, thereby rendering the furnace practicallysmokeless.

A further object of the invention is to provide a furnace wherein thefeed of the fuel is positive and automatic.

A further object of the invention is to provide an arrangement whereinthe bed of fuel occupies a position close to the boiler, whereby thegreatest amount of heat is utilized and made more effective in theproduction of steam.

A further object of the invention is to provide a construction whereinthe renewal. of the arch is facilitated.

A further object of the invention is to provide a grate arranged topresent practically a plane surface to the bed of coal, thereby avoidingprojecting surfaces, which are rapidly burned off.

A further object of the invention is to provide a construction whereinsifting of unconsumed portions or particles is avoided.

Other objects of the invention will appear more fully hereinafter.

\Vith these objects in View the invention consists substantially in theconstruction, combination, location, and relative arrangement of parts,all as will be more fully hereinafter set forth, as shown in theaccompanying drawings, and finally pointed out in the appended claims.

Referring to the accompanying drawings and to the various views andreference-signs appearing thereon, Figure 1 is a view in front elevationof a steam-boiler furnace, parts being broken out, embodying theprinciples of my invention. Fig. 2 is a vertical longitudinal sectionalview of the same. Fig. 3 is a detached detail view, in side elevation,illustrating a form of apparatus for effecting a positive and automaticfeed of the fuel. Fig. 4 is aplan View of the same. Fig. 5 is a planview of the fuel-feeding shovels. Fig. 6 is a side view of the same.

The same part is designated by the same reference-sign wherever itoccurs throughout the several views of the drawings.

In the accompanying drawings, referencesign A designates thesteam-boileigwhich may be of water-tube or tubular form, as shown, or ofany other convenient or well-known form, and suitably supported in anyconvenient manner, as the usual brick or masonry work B and thesupporting-beam O.

Adjacentto the front end of the boiler A and in proximity to the frontwall of the furnace-chain berI arrange the fire-arch D. This lire-archis peculiarly constructed with special reference to securing economy inthe consumption of coal, efiiciency in effecting a consumption of theproducts of combustion, and facility in feeding the fuel to the furnaceand in the arrangement of the bed of fuel in close proximity to thesurface to be heated and to the facility of renewal and repairs. Inorder to secure these desirable ends, I removably mount in the sidewalls of the furnacechamber the straight parallel flanged rails or barsE, and 1 string thereon the fire-bricks F, shaped to fill the spacesbetween the webs and flanges of adjacent rails E, by which saidfire-bricks are supported. The fire-bricks F are provided with channelsor passages Gfor the circulation of air-currents. By this constructionit will be seen that the under surface of the arch lies in a singlehorizontal plane, and hence I am enabledto effect a feeding of the fuelto the furnace-chamber at a point nearer to the boiler to be heated thanwould be possible otherwise. It will also be seen that in case thefire-bricks burn out on account of the intense heat to which they aresubjected an easy renewal thereof may be readily effected by withdrawingendwise one or more of the supporting-rails E through the openingprovided for that purpose in the side walls of the furnace, as indicatedin Fig. 2, and stringing new fire-brick upon such supporting-rails, aswill be readily seen and understood.

I will now describe the construction for feedin g the coal to thefurnace-chamber.

Suitably supported upon the front of the furnace-chamber is a hopper H,adapted to receive the coal to be fed to the f u rnace-chamber andhaving its outer wall curved downwardly and inwardly toward the apertureor opening in the front wall J of the furnace, through which the coalpasses into the furnace-chamber. It frequently occurs when thereceiving-hopper His filled that the coal clogs itself therein and isthereby prevented from feedingfreelyinto the furnace-chamber. The coalthus clogged may be loosened bya blow upon the outside of the hopper;but it may occur that through the inattention of the fireman the clog isnot observed. It is therefore of in] portan cc to provide some means bywhich the clogging of the coal is automatically prevented. I accomplishthis result by mounting in the aperture forming the communicationbetween the hopper H and the furnace-chamher a revoluble shaft,cylinder, or drum K, having a series of radiating arms L mountedthereon. Now by imparting to the shaft or cylinder K an intermittent orperiodic rotation the arms L effect such an agitation of the coal at thebase of the pile contained in the hopper as to prevent the coal fromcloggin g up the passage, thereby permitting a constant and free feed ofthe coal into the furnace-chamber.

I will presently describe more fully the construction and arrangement ofapparatus for actuating the shaft or drum K intermittently orperiodically.

It will be observed that the curvature of the outer wall of the hopperdownwardly and inwardly toward the f urnace-chambers assists indestroying the tendency of the coal to clog up and also cooperates withthe agitatingdrum to the same effect.

From the hopper H the coal is delivered upon a flat platform M withinthe furnace-chamber, where it piles up and from which it is fed to thegrate-bars, as will be presently more fully explained.

From the foregoing description it will be seen that in my peculiarconstruction and arrangement I am enabled to provide the platform orreceiving-table II with a fiat horizontal surface the entire lengththereof, and by constructing the fire-arch D with the fire-bricks Fthereof presenting an under surface, which also lies in a horizontalplane, a uniform distance between the platform M and the firebrick ismaintained throughout, thereby enabling me to bring the pile of coal incloser proximity to the boiler to be heated than would be possibleotherwise.

Immediately underneath the coal-receivin g platform M is arranged an airbox or chamber N, into which a draft of air may be forced from anysuitable source and in any suitable manner, as through pipe 0, and thetop wall of such chamber, which is the coal-receiving platform M, issuitably perforated, as shown, to permit the air to be forced into andthrough the pile or bed of coal supported upon the platform IWI. Anyashes, dirt, or dust which may fall into the air-chamber N may bereadily removed therefrom by removing the plate P from the bottomthereof, as will be readily understood.

From the foregoing description it will be seen and understood that thegreatest amount of heat of the coal supported upon the receiving-platform M is at the top of the pile or heap which is in closestproximity to the under surface of the fire-bricks F, and, as will beunderstood by persons familiar with the art, these bricks are maintainedat a very high temperature. Now the fresh or green coal supplied to thefurnace is introduced at a point forming the base of the heap or pile,and hence the smoke and unburned particles of carbon risin g therefromis of necessity compelled to pass through or over the entire bed of thefuel superimposed thereon and which, as above explained, increases inthe degree of heat generated thereby toward the top of such pile orheap, the said smoke and unburned particles of carbon being suppliedwith oxygen to effect its complete combustion and consequent consumptionfrom the air introduced from or through the air box or chamber N. Ifsuch smoke and unburned carbon is not consumed and destroyed whilepassing through the constantly-increasing heat of the pile as it risesthrough such pile, it is completely and effectively consumed when itcomes into contact with the intensely-heated fire wall or brick F in thepresence of the air admitted through perforations G.

It is important to provide means for positively feeding the coal fromthe platform or receiving-table M to and upon the grate-bars. Itherefore mount a series of shovel-shaped plates Q upon such platform toslide or reciprocate thereon and having the thinner edge thereofpresented toward the outer or front wall J of the furnace-chamber. Theseplates or shovels Q, more clearly shown in Fig. 6, are provided withbosses or thimbles R, by which they are held upon a rod S. Byreciprocatin g or moving the rods S toward the front wall J of thefurnace-chamber the plates slide underneath the pile or stream ofincreasing fresh or green coal, and upon the movement of said rods inthe opposite direction said coal is carried or fed forward onto thegrate-bars. In the form shown, to which, however, I do not desire to belimited or restricted, I provide four such rods S, (see Fig. 1,) and Imount two shovels or plates Q upon each rod S. In order to preventbreakage of the parts in case lumps or particles of coal should fallbetween the outer edge of the plates Q and the inner surface of the wallJ, I mount the rods S to be reciprocated outwardly through a yieldingresistance secured through a suitable spring T, interposed between acollar carried by said rod and the bar or plate V, by which said rodsare reciprocated. The nuts V serve to adjust the tension of said spring.I will presently describe more fully the arrangement of gearing forimparting to said rods S their reciprocating movements.

I will now describe the construction, f unction, and mode of operationof the grate-bars.

From the platform or table M the coal is delivered upon the top surfaceof the grate-bars 10 11. In order to facilitate the feed of the coaldown the surface formed by the gratebars, I preferably arrange the topsurface of such grate-bars upon a downward incline from the delivery endor edge of the platform. I

therefore mount a supportin g-bracket 13,with

its front end arranged to be supported upon a convenient part of theframing, say the casing forming the air box or chamber N, as indicatedat 14:, and arrange such box or sup port on a downward incline therefromand support the opposite end thereof in a convenient part of the masonryor brickwork B, as at 15. Upon the supporting-bars 13 the gratebars 1011 are pivotally supported. Each grate-bar is provided with a portion16, presenting a flat surface, and a portion 17, presenting arearwardly-inclincd surface when the grate-bar is in its normalposition, as clearly shown in the drawings. A bar 18 is arranged topivotally connect two or more of the grate-bars. In the form shown, towhich, however, I do not desire to be limited or restricted, eachalternate grate-bar is coupled to rock in unison through the bar 18. Byreciprocating the bar 18 endwise it will be seen that these grate-bars,which are connected to said bar 18, are rocked about their pivots and inthe direction of the incline upon which the top or supporting surfacesof such grate-bars are arranged, as indicated in lines in Fig. 2. Byreason of the fact that the extreme lower end of the portion 17 of thegrate-bar moves on a shorter radius about the pivot of the grate-barthan the upper portion 16 of such bar, it will be observed that the topsurface of the grate-bar or at least that inclined portion 17 thereofimparts a pushing effect to the bed of coal supported thereby, and henceurges or positively feeds the coal down the inclined surface of thegrate. It-will also be seen that the toe or extreme lower tip of theinclined portion 17 of the grate-bar when said grate-bar is rockedeffects a scraping of the fiat portion 16 of the grate-bar immediatelybelow it, thereby clearing out any particles of coal, clinker, or ashesthat may accumulate upon such flat portion, and hence maintaining a freeair-space between adjacent grate-bars.

Suitably pivoted at the extreme lower end of the grate-surface upon theadjacent brick or masonry work B is the ash-dump 19. A

rod 20 is connected to such dump 19, and eX- tending forwardly withitsouter end projecting through the front wall J of the furnace chamberaffords means for dropping said dump to remove the ashes collectedtherein. The rods 20 pass through suitable openings in the wall J andare notched at suitable points, whereby they may be maintained inposition to hold the ash-dump 19 in elevated position, as shown in Fig.2, or in the lowered or tilted position, as will be readily understood.

I will now describe an illustrative form of means for actuatingpositively and automat-.

ically the several movable parts, as above indicated.

Any suitable form of motor 21 is arranged to effect a continuousrotation of a shaft 22 through suitable gearing, as shown in Fig. 1.Upon shaft 22 is mounted gears 23, arranged to mesh with and drive gears26 upon a shaft 27. Upon the face of the gears 26 is formed a cam-flange24, as clearly shown in Fig. 3. A bar or link 25 is pivotally connectedat its inner end to bar 18 and is arranged to engage the cam-flange 24.A convenient arrangement of such engagement is to provide said link 25with rollers 28 29, arranged to receive the cam-flange 24 therebetween.From this construction it will be seen that when said gear 26 is rotatedthe cam-flange 24 thereon effects a reciprocation of link 25, which inturn imparts a reciprocating movement to bars 18, and hence effects aperiodic rocking of the grate-bars, as above explained. By providing oneor more pairs of such links 25 and bars 18 and relatively timing theaction and operation of the cams 24, I thus secure a rocking or pushingmovement of the entire grate-surface, and hence an efficient feed of thecoal. The degree to which the grate-bars are rocked may be rigidlyadjusted by adj usting the rollers 28 29 relative to each other, as bymounting one of said rollers in a slot 30 in said link 25.

To the opposite face of the gears 26, and eccentrically with referenceto the axis of rotation thereof, I pivotally connect, as at 32, one endof an arm or link 81 and I connect the outer end of such link to a lever33, which is pivotally mounted, as at 3-.t, upon a convenient portion ofthe framework. The levers 33 are connected to or form part of the bar orplate V, above mentioned. Therefore when the gears 26 are rotated alateral vibration or movement is imparted to said bar or plate V, andhence therethrough a reciprocation is imparted to rods S, upon which theshoes or plates Q are carried, as above explained.

The plate or bar V is provided with an arm or pawl 35, arranged toengage a ratchet-wheel 36 upon the end of the shaft or cylinder K,whereby a periodic or intermittent rotation is imparted to said shaft toeffect an agitation of the coal at the base of the hopper H.

Many variations and alterations in the details of construction andarrangement of parts would readily suggestthemselves to persons skilledin the art and still fall Within the spirit and scope of my invention. Ido not desire, therefore, to be limited or restricted to the exactdetails shown and described; but,

Having now explained the nature and objeet of my invention and anoperative embodiment thereof, and having explained the construction,function, and mode of operation thereof, what I claim as new and usefuland of my own invention, and desire to secure by Letters Patent, is

1. In a boiler-furnace, a furnace-chamber, a series of suspendedsupporting-rails arranged within said chamber and in the same horizontalplane and in advance of the front ends of the grate-surface, andremovable bricks arranged to be supported by said rails, said brickspresenting a fiat under surface; as and for the purpose set forth.

2. In a lire-arch for boiler-furnaces, a f urnace-chamber, grate-barsarranged therein,

1 a receiving-platform for the coal arranged in said chamber and inadvance of the gratebars, supporting-rails arranged within said chamberand above said platform and in advance of the grate-bars, andfire-bricks removably supported on said rails and arranged to present aflat under surface parallel with the supporting-surface of saidplatform; as and for the purpose set forth.

3. In a fire-arch for boiler-furnaces, a furnace-chamber, grate-barsarranged therein, a receiving-platform for the coal arranged in saidchamber and in advance of the gratebars, supporting-rails arranged abovesaid platform parallel with each other and in a plane parallel with thesupporting-surface of said platform, and fire-bricks removably supportedon said rails and presenting an under surface parallel with thesupporting-surface of said platform, said bricks provided withair-passages as and for the purpose set forth.

4. In a boiler-furnace, the combination with grate-bars, a perforatedplatform arranged within the furnace-chamber and adapted to receivethereon the fresh or green coal, said grate-bars having their front endsarranged adjacent to the delivery edge of said platform and extendingrearwardly therefrom upon a downward incline, an air-passage arrangedadjacent to said platform and adapted to deliver air to the coalsupported on said platform through said perforations; as and for thepurpose set forth.

5. In a boiler-furnace, the combination with the grate-bars,a perforatedplatform arranged within the furnace-chamber and adapted to receivethereon the fresh or green coal, said grate-bars having their front endsarranged adjacent to the delivery edge of said receiving-platform andextending rearwardly therefrom upon a downward incline, an air-chamberarranged adjacent to said platform and adapted to deliver air to thecoal supported on said platform through said perforations, saidair-chamber provided With a removable plate; as and for the purpose setforth.

6. In a boiler-furnace, the combination with grate-bars, of a platformarranged within the furnace-chamber and in advance of the gratebars,said platform adapted to receive thereon the fresh or green coalsupplied to said chamber, pushers arranged to reciprocate 011 saidplatform to positively feed the fresh or green coal from said platformto said gratebars, a lever pivotally mounted at one end upon the frontof the furnace-chamber and connected at the opposite end thereof to saidpushers, and means, connected intermediate the ends of said lever, forrocking the same and actuating said pushers; as and for the purpose setforth.

7. In aboiler-furnace,the combination with the grate-bars, of a platformarranged in the furnace-chamber to receive thereon the fresh or greencoal supply to said chamber, reciprocatory plates mounted on saidplatform to feed said coal, and means for actuating said plates; as andfor the purpose set forth.

8. In a boiler-furnace, aplatform arranged within the furnace-chamber,to receive thereon the fresh or green coal, shovel-shaped plates havingtheir thin edges presented out- \vardly arranged to slide back and forthupon said platform to positively feed the coal to the grate-surface ofthe furnace, and means for reciprocating said plates against a yield ingresistance; as and for the purpose set forth.

9. In a boiler-furnace, a series of pivotallymounted grate-bars, eachgrate-bar provided with a flat portion and with a rearwardly-inclinedportion, and means for rocking said grate-bars; as and for the purposeset forth.

10. In a boiler-furnace, a series of pivotallymounted grate-barsarranged to present a continuously rearwardl'y-inclined grate-surface,and means for simultaneously rocking one or more of said grate-bars; asand for the purpose set forth.

11. In a boiler-furnace,a series of pivotallymounted grate-bars,arranged with reference to each other to form air-spaces therebetween,and means for intermittently rocking one or more of said grate-bars; asand for the purpose set forth.

12. In a boiler-furnace,aseries of pivotallymounted grate-bars, eachprovided with a grate-surface having a flat horizontal portion and arearwardly-inclined portion, bars connecting two or more of suchgrate-bars, and means for intermittently and positively reciprocatingsaid connecting bars endwise; as and for the purpose set forth.

13. In a boiler-furnace, a shaft, means for rotating said shaft, camsmounted on said shafts, a series of 'pivotally-mounted gratebarsarranged to present a flat rearwardlyinclined surface, and meansactuated by said cams for rocking said grate-bars about their pivots; asand for the purpose set forth.

14:. In a boiler-furnace, ashaft having gears thereon, means forrotating said shaft, camfianges formed on said gears, a series ofpivotally-mounted grate-bars, means for positively rocking saidgrate-bars about their by said crank, a bar carryinga pawl arranged tobe actuated by said lever, a hopper, a shaft or drum mounted therein andhaving arms projecting therefrom, a ratchet-Wheel mounted on said shaftand arranged to be engaged and intermittently rotated by said pawl; asand for the purpose set forth.

In Witness whereof I have hereunto set my hand this 20th day of May,1896, in the pres ence of the subscribing Witnesses.

WILLIAM H. PEARCE.

itnesses:

MICHAEL I. GAVANAGH, E. O. MORGAN.

